Dvd 18

Conventional dual-layer DVDs store one layer of data on each side of the disc; the DVD player's laser simply changes focus at the end of the first side, and begins reading the second side (through the transparent glue used to bond the two layers together). Unlike DVD-9 discs, the two layers on each side of a DVD-18 are not located on opposite sides of the disc. The first layer of data is actually embedded within the disc's upper polycarbonate substrate (plastic surface layer), while the second layer is located where the first layer would normally be found on a conventional DVD-9 disc.

This process requires much more care when manufacturing than conventional DVDs, making DVD-18s more expensive to produce than conventional single-sided single-layer (DVD-5) or single-sided dual-layer (DVD-9) DVDs. The first DVD-18 released in North America was Artisan's The Stand.